Performance evaluation for frequency response services from miscellaneous energy resources

Abstract

The phase out of conventional synchronous generators (SGs) and the vigorous development of renewable energy sources (RESs) are indisputably leading to a significant reduction in the inertia of power grids, blowing a hole in frequency security and stability. To address this issue, various fast-acting resources such as battery energy systems (BESS) are being discussed worldwide. Accurate quantifying the relative effectiveness of these resources in arresting frequency decline to conventional methods is, therefore, of great significance to securely operate low-inertia power systems (LIPS). To do so, an analytical model of the equivalent frequency-containment performance ratio (EFCPR) is proposed for heterogeneous resources having different response characteristics. Furthermore, two Sigmoid-function-based approaches are also proposed to extend the EFCPR model to aggregated resources, and a more general scenario taking delivery time instant of instantaneous response BESS into account. Numerical results on the Texas test case and the Great Britain power grids with real operation data (from September 2023 to December 2024) collected from the National Energy System Operator (NESO) website validate the EFCPR model and penetrate many of the parameters' impacts.